TW200529273A - Controlling carbon nanotubes using optical traps - Google Patents

Controlling carbon nanotubes using optical traps Download PDF

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Publication number
TW200529273A
TW200529273A TW093139843A TW93139843A TW200529273A TW 200529273 A TW200529273 A TW 200529273A TW 093139843 A TW093139843 A TW 093139843A TW 93139843 A TW93139843 A TW 93139843A TW 200529273 A TW200529273 A TW 200529273A
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Taiwan
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laser beam
cnt
patent application
item
layer
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TW093139843A
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Chinese (zh)
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yue-gang Zhang
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Intel Corp
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y20/00—Nanooptics, e.g. quantum optics or photonic crystals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/50—Containers for the purpose of retaining a material to be analysed, e.g. test tubes
    • B01L3/502—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures
    • B01L3/5027—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip
    • B01L3/502761—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip specially adapted for handling suspended solids or molecules independently from the bulk fluid flow, e.g. for trapping or sorting beads, for physically stretching molecules
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S977/00—Nanotechnology
    • Y10S977/70—Nanostructure
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S977/00—Nanotechnology
    • Y10S977/70—Nanostructure
    • Y10S977/734—Fullerenes, i.e. graphene-based structures, such as nanohorns, nanococoons, nanoscrolls or fullerene-like structures, e.g. WS2 or MoS2 chalcogenide nanotubes, planar C3N4, etc.
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S977/00—Nanotechnology
    • Y10S977/70—Nanostructure
    • Y10S977/734—Fullerenes, i.e. graphene-based structures, such as nanohorns, nanococoons, nanoscrolls or fullerene-like structures, e.g. WS2 or MoS2 chalcogenide nanotubes, planar C3N4, etc.
    • Y10S977/742—Carbon nanotubes, CNTs
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S977/00—Nanotechnology
    • Y10S977/84—Manufacture, treatment, or detection of nanostructure
    • Y10S977/842—Manufacture, treatment, or detection of nanostructure for carbon nanotubes or fullerenes

Abstract

An embodiment of the present invention is a technique to control carbon nanotubes (CNTs). A laser beam is focused to a carbon nanotube (CNT) in a fluid. The CNT is responsive to a trapping frequency. The CNT is manipulated by controlling the focused laser beam.

Description

200529273 (1) 九、發明說明 【發明所屬之技術領域】 本發明之實施例係有關半導體之領域’尤係有關奈米 技術。 【先前技術】 奈米碳管是奈米技術中極有前途的元件。奈米碳管是 包含石墨圓柱的與碳60 ( fullerene )相關之結構。可（藉 由將分子的某部分依附到奈米碳管而）將奈米碳管機能化 ，以便增加奈米碳管在溶劑中之溶解度，並控制奈米碳管 與其他分子或固體材料間之親和力。 目前用來進行奈米碳管分離的方法是離心機、以及基 於化學親和力的液體色層分析法。係在介電泳動（ dielectrophoresis )中之電極邊緣上執行陷阱捕獲。對於 奈米碳管操控而言，現有的方法係基於掃描探針顯微鏡以 及直流（D C )或交流（A C )電場對準。這些技術的精確 性及使用彈性不夠，因而無法用於各種應用。 【發明內容】 本發明的一實施例是一種控制奈米碳管（Carbon NanoTube ;簡稱CNT )的技術。將一雷射光束聚焦在一 流體中之奈米碳管（CNT )。該CNT對一捕獲頻率起響 應。藉由控制該被聚焦的雷射光束而操控該CNT。 200529273 (2) 【實施方式】 本發明的一實施例是一種控制奈米碳管（CNT )的技 術。將一雷射光束聚焦在一流體中之奈米碳管（CNT)。 該CNT對一捕獲頻率起響應。藉由控制該被聚焦的雷射 光束而操控該CNT。 在下文的說明中，述及了許多特定的細節。然而，我 們當了解，無可在沒有這些特定的細節之情形下實施本發 明的實施例。在其他的情形中，並未示出習知的電路、結 構、及技術，以便不會模糊了對該說明的了解。 可以通常被示爲一流程表、流程圖、一結構圖、或一 方塊圖的一程序來說明本發明之一實施例。雖然一流程圖 可以一循序程序之方式說明各作業，但是可以並行或同時 之方式執行許多該等作業。此外，可重新安排該等作業的 順序。當完成了一程序之作業時，即終止該程序。一程序 (process )可對應於一方法、一程序（procedure )、以 及一製造（manufacturing)或製造（fabrication)方法等 的術語。 圖1示出可實施本發明的一實施例之一系統（100) 。系統（100 )包含一雷射（1 10 )、一光學組合件（120 )、及一流體（1 3 0 )。 雷射（1 1 0 )經由光學組合件（1 20 )而將一雷射光束 (125)聚焦在處理室（130)。可將雷射（110)控制成 具有若干工作模式。可將雷射（1 1 0 )控制成具有各種強 度及光頻率。可將雷射（1 1 0 )偏振。 -5- 200529273 (3) · 光學組合件（120 )提供了用來處理雷射光束（12 5 ) 的若干光學元件。該等光學元件的例子包括繞射光學元件 '透鏡、望遠鏡頭、光調變器、及濾光片。光學組合件（ 120)將雷射光束（125)導向流體（130)中之奈米碳管 (CNT )。 流體（1 3 0 )包含多層或多通道的不同流體。可將奈 米碳管包含在由玻璃或聚合物材料構成之一流體通道或容 器中。流體（130)包含若干CNT( 135^135]^)。該等 CNT 可以是單壁 CNT( Single-Walled CNT;簡稱 S WNT )、或多壁 CNT (Multi-Walled CNT;簡稱 M WNT )。可 將該等CNT機能化。 系統（1〇〇)可以若干種方式控制流體（130)中之該 等CNT。該操控包括：捕獲若干類別的CNT ;移動一被 捕獲的CNT ;釋出一被捕獲的CNT ;以及對準被捕獲的 CNT。將雷射（110)用來操控CNT係根據光偶極阱（ optical dipole trap)的觀念。 被聚焦的一雷射光束可利用該雷射光束的電場與一中 性粒子或分子中被感應的自發偶極矩間之相互作用而不或 該中性粒子或分子。可以下式表示一雷射光束的電場中之 一中性粒子的被感應之偶極矩： Ρ= ε 〇 X E ( 1 ) 其中P是每一單位體積的偏振或偶極矩，£ ο是自由 空間的介電係數，％是介質極化率、且E是電場。 可以下式表示位能： -6 - 200529273 (4) U= ( -1/2 ) <P.E>= ( -1/2 ) ε 〇% <E>2 ( 2) 可以下式而以複數的形式將介質極化率表示爲頻率的 一函數： X ( ω ) = χ ^ ( ω ) χ ^ (ω) (3) 其中；是實數部分，且％ 〃 （ω)是虛數部 分。 當ω<ω〇時，λ：’（ ω ) >〇，其中是一諧振頻率 〇 可自方程式（2 )推導出··當光強度增加時，位能U 減少。此外，粒子傾向移到較高Ε的一區域，並在一雷射 光束的中心上被捕獲，其中係假設該雷射光束的光強度分 佈爲高斯分佈。 視直徑及手徵性（chirality)而定，一 SWMT可以是 金屬或半導體。係由被稱爲van Hove奇異點（van Hove Sigularity )的許多尖峰構成一 SWNT的電子狀態密度。 該等對應的van Hove奇異點間之能隙是在光學上容許的 能帶間躍遷能。藉由選擇一適當的雷射頻率或持續地調整 雷射頻率，即可捕獲某一類型的奈米碳管。M WNT是一種 具有不同的直徑及手徵性的多個SWNT之組合件。對一 MWNT的捕獲係取決於該 MWNT的成分，亦即不同 SWNT類型間之比率。可捕獲所有類型的SWNT之一雷射 頻率亦可捕獲MWNT。 亦可利用一偏振雷射光束對準各奈米碳管。偶極必然 與奈米碳管的軸平行。可將偏振P分解爲一平行的分量 200529273 (5)200529273 (1) IX. Description of the invention [Technical field to which the invention belongs] Embodiments of the present invention relate to the field of semiconductors', and more specifically to nanotechnology. [Previous technology] Nano carbon tube is a very promising element in nano technology. Nano carbon tubes are carbon 60 (fullerene) related structures containing graphite cylinders. Functionalization of the carbon nanotubes (by attaching a portion of the molecule to the carbon nanotubes) to increase the solubility of the carbon nanotubes in the solvent and control the relationship between the carbon nanotubes and other molecules or solid materials Affinity. The methods currently used for carbon nanotube separation are centrifuges and chemical affinity-based liquid chromatography. Trap capture is performed on the edges of the electrodes in dielectrophoresis. For the control of carbon nanotubes, existing methods are based on scanning probe microscopy and direct current (DC) or alternating current (AC) electric field alignment. These technologies are not precise enough or flexible enough to be used in a variety of applications. SUMMARY OF THE INVENTION An embodiment of the present invention is a technology for controlling a carbon nano tube (Carbon NanoTube; CNT for short). A laser beam focuses a nano carbon tube (CNT) in a fluid. The CNT responds to a capture frequency. The CNT is manipulated by controlling the focused laser beam. 200529273 (2) [Embodiment] An embodiment of the present invention is a technology for controlling a carbon nanotube (CNT). A carbon nano tube (CNT) that focuses a laser beam in a fluid. The CNT responds to a capture frequency. The CNTs are manipulated by controlling the focused laser beam. In the following description, many specific details are mentioned. However, we should understand that it is not possible to implement the embodiments of the present invention without these specific details. In other instances, well-known circuits, structures, and techniques have not been shown so as not to obscure the description. An embodiment of the present invention may be illustrated by a program that is generally shown as a flowchart, a flowchart, a structure diagram, or a block diagram. Although a flowchart can describe each job in a sequential manner, many of these jobs can be performed in parallel or simultaneously. In addition, the order of such operations can be rearranged. When a procedure is completed, the procedure is terminated. A process may correspond to terms such as a method, a procedure, and a manufacturing or manufacturing method. FIG. 1 illustrates a system (100) according to an embodiment of the present invention. The system (100) includes a laser (1 10), an optical assembly (120), and a fluid (130). The laser (1 1 0) focuses a laser beam (125) on the processing chamber (130) via the optical assembly (1 20). The laser (110) can be controlled to have several operating modes. The laser (1 1 0) can be controlled to have various intensities and light frequencies. Laser (1 1 0) can be polarized. -5- 200529273 (3) · The optical assembly (120) provides several optical elements for processing the laser beam (12 5). Examples of such optical elements include diffractive optical elements' lenses, telescope lenses, light modulators, and filters. The optical assembly (120) directs the laser beam (125) to a nano carbon tube (CNT) in the fluid (130). The fluid (130) contains multiple or multiple channels of different fluids. The carbon nanotubes can be contained in a fluid channel or container made of glass or a polymer material. The fluid (130) contains several CNTs (135 ^ 135) ^). The CNTs may be single-walled CNT (S-WNT) or multi-walled CNT (M-WNT). These CNTs can be functionalized. The system (100) can control these CNTs in the fluid (130) in several ways. The manipulation includes: capturing several types of CNTs; moving a captured CNT; releasing a captured CNT; and aligning the captured CNT. The laser (110) is used to control the CNT system according to the concept of an optical dipole trap. A focused laser beam may use the electric field of the laser beam to interact with the induced spontaneous dipole moment in a neutral particle or molecule instead of the neutral particle or molecule. The induced dipole moment of a neutral particle in the electric field of a laser beam can be expressed as: P = ε 〇XE (1) where P is the polarization or dipole moment per unit volume, and £ ο is free The dielectric constant of space,% is the dielectric polarizability, and E is the electric field. Potential energy can be expressed by the following formula: -6-200529273 (4) U = (-1/2) < P.E > = (-1/2) ε 〇% < E > 2 (2) The dielectric polarizability is expressed as a function of frequency in the form of a complex number: X (ω) = χ ^ (ω) χ ^ (ω) (3) where; is the real part and% ％ (ω) is the imaginary part. When ω < ω0, λ: '(ω) > 〇, which is a resonance frequency 〇 can be deduced from the equation (2) · When the light intensity increases, the potential energy U decreases. In addition, particles tend to move to a region of higher E and are captured at the center of a laser beam, where it is assumed that the light intensity distribution of the laser beam is Gaussian. Depending on the diameter and chirality, a SWMT can be metal or semiconductor. It consists of many peaks called van Hove singularity (van Hove Sigularity), which constitutes a SWNT's electronic state density. The energy gap between these corresponding van Hove singularities is the optically allowable transition energy between bands. By selecting an appropriate laser frequency or continuously adjusting the laser frequency, a certain type of carbon nanotube can be captured. M WNT is a combination of multiple SWNTs with different diameters and chirality. The capture of a MWNT depends on the composition of the MWNT, that is, the ratio between different SWNT types. Capable of capturing one of all types of SWNT laser frequencies and MWNT. A polarized laser beam can also be used to align the carbon nanotubes. The dipole must be parallel to the axis of the carbon nanotube. Polarization P can be decomposed into a parallel component 200529273 (5)

Pp及一正交的分量P。： P = Pp + P0 三Ρρ= ε ο X Ep ( 4 ) 其中Ep是E的平行分量。 然後可以下式表示位能： U= ( -1/2 ) <Ρ·Ε>= ( -1/2) <Ep>2cos0 ( 5) 其中0是E與一 CNT的軸間之角度。 自以上各方程式可知，E的增加將導致U的減少。此 外，當ω<ω〇，χ / (ω)>0時，0的減少將導致U的 減少。因此，偏振雷射光束可捕獲各CNT，並對準該等 CNT。 圖2示出對根據本發明的一實施例的CNT之操控。 流體（130)包含一第一層（210)、一緩衝層（220)、 以及一第二層（230 )。 這三層（210 ) 、 （ 220 )、及（23 0 )是層流（ laminar flow )層。緩衝層（220 )防止第一層（210 )與 第二層（23 0 )間之CNT的隨機擴散。第一層（210)包 含若干自由CNT ( 135!— 135N)。 雷射光束被聚焦，以便捕獲第一層（210)中在部位 (240 )上的CNT ( 135k )。係在被稱爲捕獲頻率的一特 定頻率下將該雷射光束聚焦，以便選擇性地捕獲/釋出對 該捕獲頻率起響應的CNT(135k)。一旦捕獲了 CNT( 135k)之後，即可藉由控制該雷射光束，而移動並釋出 CNT ( 135k)。 爲了移動CNT ( 135k )，將雷射的焦點位置自部位（ 200529273 (6) 240)改變至第二層（230)中之一部位（250)。可精確 地移動該雷射，因而可精確地控制CNT ( 1 35k )的移動。 一旦將CNT ( 1 35k )移到一個新位置之後，即可釋出CNT (135k )。 可使用若干種方法而在第一層（210)或第二層（230 )的任何位置（例如，部位（240 )或（2 5 0 ))上釋出被 捕獲的CNT ( 135k)。在第一種方法中，只需關掉雷射（ 110)，而切斷雷射光束。電場被移除，且CNT ( 135k) 變爲自由狀態。在第二種方法中，以一光學或機械阻隔器 阻隔雷射光束。在第三種方法中，在光學組合件（1 20 ) 或雷射（1 1 0 )本身中使用一濾光片，而減少雷射強度。 在第四種方法中，將雷射（110)的頻率改變爲與捕獲頻 率不同的頻率。在第五種方法中，以具有與第一層（210 )不同的黏度或介電常數之另一流體取代第二層（230) 中之流體。在第六種方法中，雷射光束移動通過一液體-固體介面（例如，一微流體通道的壁）。 可使雷射光束的拂掠與釋出CNT的事件同步，而持 續地執行CNT的釋出。 圖3示出可根據本發明的一實施例而使用具有不同黏 度的若干層來操控CNT。該流體具有三層（310) 、（320 )、及（3 3 0 )。 雷射光束被聚焦在第一層（310)中之CNT。係在部 位（340 )上以光學方式捕獲CNT ( 135 )。可移動雷射光 束，而將被捕獲的CNT ( 135 )移到第二層（3 2 0 )的部位 -9 - 200529273 (7) (350)。然後，當CNT(135)上因第三層（330)而產 生的剪力大於雷射捕獲力時，即在具有不同黏度的兩個層 流層（320)及（330)之介面上釋出該被捕獲的CNT( 135) ° 該雷射光束可在部位（340)與第三層（3 3 0 )中之一 部位（3 60 )之間來回拂掠，以便捕獲、移動CNT ( 135) ，並在第二層（320)與第三層（330)之間的介面上釋出 CNT ( 135 )。此種技術無須調變雷射的強度或改變頻率 ，即可釋出CNT。 圖3中之一極端例子是第三層（330)是一固體（例 如，一微流體通道的一壁）。 圖4示出根據本發明的一實施例而使用偏振雷射光束 來操控CNT。流體（130)包含第一及第二層（410)及（ 420 )。一層（ 440 )是一固體基材（例如，玻璃、矽）。 可在基材（ 440 )上覆蓋一黏著層（ 43 0 )。 雷射光束在第一層（410)的一部位（450)上捕獲 CNT ( 135 ) 。CNT ( 135 )對一偏振起響應。該雷射是一 偏振的雷射。CNT ( 135 )對準該偏振雷射光束所提供的 方位。藉由相應地改變雷射焦點的位置，而將被捕獲的 CNT ( 135 )移到第二層（420 )的部位（460 )。然後在 第二層（420)與黏著層（430)之間的表面上釋出被捕獲 的CNT ( 135 )黏著層（43 0 )提供對被釋出的CNT ( 135 )之支承。 黏著層（43 0 )在使CNT ( 135)對準或朝向與雷射偏 -10- 200529273 (8) 振方向相同的方向時，也使CNT ( 135 )不能移動。可以 微影方法在黏著層（430 )中產生圖樣，以便進一步限定 CNT ( 135 )可附著的位置。 如果被捕獲的CNT (135)具有與基材（ 44 0)的表面 間之高親和力，則黏著層（43 0 )不是必要的，且可以基 材層（440 )執行使CNT ( 135 )無法移動。 第二層（420 )的功能是使CNT不會隨機擴散到黏著 層（430)或基材層（440)。如果第一層（410)中之 CNT濃度被稀釋到足以忽略表面（ 430 )或（ 440 )上的非 特定結合力，則第二層（420 )不是必要的。 可將基材層（440 )的表面機能化，以便在將CNT ( 135 )對準或朝向相同方向時，使CNT ( 135 )無法移動。 可以若干種方式執行上述步驟。例如，可以由當接近該表 面時可結合到 CNT ( 135 )或機能化的CNT ( 135 )上的 官能基或化學分子的某部分的帶正電之分子構成的一層（ 430 )(例如，自行組合的3 -胺基丙基三乙氧基矽烷單 層）覆蓋基材層（440)。 雷射光束可在部位（450 )與基材層（440 )中之一部 位（4 7 0 )之間來回拂掠，以便捕獲、對準、移動、釋出 、及沈積（使之無法移動）基材層（44〇)上的CNT ( 135 )° 雖然已參照數個實施例而說明了本發明，但是對此項 技術具有一般知識者當可了解’本發明並不限於所述的該 等實施例，而是可在最後的申請專利範圍的精神及範圍內 -11 - 200529273 (9) 明視爲例示性而 以修改及改變實施本發明。因而應將笨說 非限制性。 【圖式簡單說明】 發明的實施例之 的了解。在該等 一系統。 CNT之操控。 實施使用具有不 用偏振雷射光束 可參照前文中之說明以及用來解說本 各附圖，而對本發明的該等實施例有最佳 圖式中： 圖1示出可實施本發明的一實施例之 圖2示出對根據本發明的一實施例的 圖3示出可根據本發明的一實施例而 同黏度的若干層來操控CNT。 圖4示出根據本發明的一實施例而使 來操控CNT。 【主要元件符號說明】 100 :系統 Π 0 :雷射 120 :光學組合件 1 3 0 :流體 1 2 5 :雷射光束 135，135P135N，135k :奈米碳管 210，310，410:第一層 220 :緩衝層 2 3 0，3 20，420 :第二層 200529273 (10) 240， 250， 340， 350， 360， 450， 460 ：部位 3 3 0 ··第三層 4 3 0 :黏著層 4 4 0 ··基材層Pp and an orthogonal component P. : P = Pp + P0 Three Pρ = ε ο X Ep (4) where Ep is the parallel component of E. The potential energy can then be expressed by the following formula: U = (-1/2) < ρ · Ε > = (-1/2) < Ep > 2cos0 (5) where 0 is the angle between E and the axis of a CNT. It can be known from the above equations that an increase in E will lead to a decrease in U. In addition, when ω < ω0, χ / (ω) > 0, a decrease in 0 will cause a decrease in U. Therefore, a polarized laser beam can capture and align each CNT. FIG. 2 illustrates manipulation of a CNT according to an embodiment of the present invention. The fluid (130) includes a first layer (210), a buffer layer (220), and a second layer (230). These three layers (210), (220), and (230) are laminar flow layers. The buffer layer (220) prevents random diffusion of CNTs between the first layer (210) and the second layer (23 0). The first layer (210) contains several free CNTs (135! —135N). The laser beam is focused in order to capture the CNT (135k) on the site (240) in the first layer (210). The laser beam is focused at a specific frequency called the capture frequency to selectively capture / release CNTs (135k) that respond to the capture frequency. Once the CNT (135k) is captured, the CNT (135k) can be moved and released by controlling the laser beam. In order to move the CNT (135k), the focus position of the laser was changed from the part (200529273 (6) 240) to one part (250) in the second layer (230). This laser can be moved precisely, so that the movement of the CNT (135k) can be precisely controlled. Once the CNT (135k) is moved to a new position, the CNT (135k) is released. Several methods can be used to release the captured CNTs (135k) at any location on the first layer (210) or the second layer (230) (e.g., the location (240) or (250)). In the first method, it is only necessary to turn off the laser (110) and cut off the laser beam. The electric field is removed and the CNT (135k) becomes free. In the second method, an optical or mechanical barrier is used to block the laser beam. In a third method, a filter is used in the optical assembly (120) or the laser (110) to reduce the laser intensity. In the fourth method, the frequency of the laser (110) is changed to a frequency different from the acquisition frequency. In the fifth method, the fluid in the second layer (230) is replaced with another fluid having a different viscosity or dielectric constant than the first layer (210). In a sixth method, the laser beam moves through a liquid-solid interface (eg, a wall of a microfluidic channel). The sweeping of the laser beam can be synchronized with the CNT release event, and the CNT release can be performed continuously. Figure 3 shows that CNTs can be manipulated using several layers with different viscosities according to an embodiment of the invention. The fluid has three layers (310), (320), and (3 3 0). The laser beam is focused on the CNTs in the first layer (310). CNTs (135) are captured optically on the part (340). The laser beam can be moved, and the captured CNT (135) is moved to the second layer (3 2 0) -9-200529273 (7) (350). Then, when the shear force generated by the third layer (330) on the CNT (135) is greater than the laser capture force, it is released on the interface of two laminar layers (320) and (330) with different viscosities. The captured CNT (135) ° The laser beam can be swept back and forth between the part (340) and one part (3 60) in the third layer (3 3 0) in order to capture and move the CNT (135) And release CNT (135) on the interface between the second layer (320) and the third layer (330). This technology can release CNT without adjusting the intensity or frequency of the laser. An extreme example in Figure 3 is that the third layer (330) is a solid (e.g., a wall of a microfluidic channel). Figure 4 illustrates the use of a polarized laser beam to manipulate CNTs according to an embodiment of the invention. The fluid (130) includes first and second layers (410) and (420). One layer (440) is a solid substrate (for example, glass, silicon). An adhesive layer (43 0) can be covered on the substrate (440). The laser beam captures CNTs (135) on a portion (450) of the first layer (410). CNT (135) responds to a polarization. The laser is a polarized laser. The CNT (135) is aligned with the orientation provided by the polarized laser beam. By changing the position of the laser focus accordingly, the captured CNTs (135) are moved to the second layer (420) (460). The captured CNT (135) adhesive layer (43 0) is then released on the surface between the second layer (420) and the adhesive layer (430) to provide support for the released CNT (135). When the adhesive layer (43 0) aligns or faces the CNT (135) with the same direction as the laser deflection -10- 200529273 (8), it also prevents the CNT (135) from moving. Lithography can be used to create a pattern in the adhesive layer (430) to further define where the CNT (135) can be attached. If the captured CNT (135) has a high affinity with the surface of the substrate (44 0), the adhesive layer (43 0) is not necessary, and the substrate layer (440) can be performed to make the CNT (135) unable to move . The function of the second layer (420) is to prevent the CNTs from randomly diffusing into the adhesion layer (430) or the substrate layer (440). If the CNT concentration in the first layer (410) is diluted enough to ignore non-specific binding forces on the surface (430) or (440), the second layer (420) is not necessary. The surface of the substrate layer (440) can be functionalized so that the CNT (135) cannot be moved when the CNT (135) is aligned or oriented in the same direction. The above steps can be performed in several ways. For example, it can consist of a layer (430) of positively charged molecules that can bind to a functional group of CNT (135) or functionalized CNT (135) or a portion of a chemical molecule when approaching the surface (e.g., by itself A combined 3-aminopropyltriethoxysilane monolayer) covers the substrate layer (440). The laser beam can be swept back and forth between the part (450) and one part (470) of the substrate layer (440) to capture, align, move, release, and deposit (making it impossible to move) CNT (135) ° on the substrate layer (44〇) Although the present invention has been described with reference to several embodiments, those with ordinary knowledge of this technology will understand that the present invention is not limited to the described The examples are within the spirit and scope of the scope of the last patent application-11-200529273 (9) The invention is clearly to be considered as illustrative and the invention can be modified and changed. It should therefore be non-limiting. [Brief description of the drawings] Understanding of embodiments of the invention. In such a system. Control of CNT. The use of the laser beam without polarization can be referred to the previous description and used to explain the drawings, and these embodiments of the present invention have the best drawings. Figure 1 shows an embodiment in which the present invention can be implemented FIG. 2 shows an embodiment of the present invention. FIG. 3 shows that the CNTs can be manipulated by several layers with the same viscosity according to an embodiment of the present invention. Fig. 4 shows that CNTs are manipulated according to an embodiment of the present invention. [Description of main component symbols] 100: System Π 0: Laser 120: Optical assembly 1 3 0: Fluid 1 2 5: Laser beam 135, 135P135N, 135k: Nano carbon tube 210, 310, 410: First layer 220: buffer layer 2 3 0, 3 20, 420: second layer 200529273 (10) 240, 250, 340, 350, 360, 450, 460: part 3 3 0 · third layer 4 3 0: adhesive layer 4 4 0 ·· Substrate layer

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Claims (1)

200529273 (1) 十、申請專利範圍 1 · 一種控制方法，包含下列步驟： 將一雷射光束聚焦在一流體中之奈米碳管（CNT )， 該CNT對一捕獲頻率起響應；以及 藉由控制該被聚焦的雷射光束而操控該奈米碳管（ CNT )。 2 ·如申請專利範圍第1項之控制方法，其中該操控 步驟包含下列步驟： 改變該雷射光束的頻率，以便配合捕獲頻率，而捕獲 在該流體中之一第一流體層中的一捕獲部位之該CNT。 3 ·如申請專利範圍第2項之控制方法，其中該操控 步驟包含下列步驟： 將該雷射光束的焦點位置自一第一位置改變至一第二 位置，而將該被捕獲的CNT自該第一層中之一第一部位 移到該流體中之一第二層中之一第二部位。 4 ·如申請專利範圍第2項之控制方法，其中該操控 步驟包含下列步驟： 以關閉該雷射光束、阻隔該雷射光束、過濾該雷射光 束以減少雷射強度、改變該雷射光束的頻率、在該第二層 中使用具有不同的黏度或介電常數之一不同的流體媒介、 以及移動該雷射光束通過一液體-固體介面中之一種方式 釋出該被捕獲的CNT。 5 ·如申請專利範圍第2項之控制方法，其中該操控 步驟包含下列步驟： -14- 200529273 (2) 在具有不同黏度的第一與第二層間之一介面上釋出該 被捕獲的CNT。 6. 如申請專利範圍第2項之控制方法，其中該操控 步驟包含下列步驟· 將該雷射光束偏振’而對準該被捕獲的CNT。 7. 如申請專利範圍第1項之控制方法，其中該操控 步驟包含下列步驟： ' 將一基材層機能化，而使該CNT無法移動。 · 8 ·如申請專利範圍第1項之控制方法，其中該聚焦步 驟包含下列步驟： 將該雷射光束聚焦到具有複數個單壁CNT ( SWNT ) 的一多壁CNT(MWNT) ，而操控該MWNT。 9. 一種控制裝置，包含： 含有一奈米碳管（CNT )的一流體，該CNT對一捕 獲頻率起響應，且係以受一雷射控制的一被聚焦之雷射光 束操控該CNT。 〇 10. 如申請專利範圍第9項之控制裝置，其中該雷射 改變該雷射光束的頻率，以便配合捕獲頻率，而捕獲在一 第一流體層中的一捕獲部位之該CNT。 11·如申請專利範圍第10項之控制裝置，其中該雷 · 射將該雷射光束的焦點位置自一第一位置改變至一第二位 - 置，而將該被捕獲的CNT自該第一層中之一第一部位移 到一第二層中之一第二部位。 1 2 ·如申請專利範圍第1 〇項之控制裝置，其中係以 -15- 200529273 (3) 關閉該雷射光束、阻隔該雷射光束、過濾該雷射光束以減 少雷射強度、改變該雷射光束的頻率、在該第二層中使用 具有不同的黏度或介電常數之一不同的流體媒介、以及移 動該雷射光束通過一液體-固體介面中之一種方式釋出該 被捕獲的CNT。 1 3 ·如申請專利範圍第1 0項之控制裝置，其中係在 具有不同黏度的該第一與第二層間之一介面上釋出該被捕 獲的CNT。 1 4·如申請專利範圍第1 0項之控制裝置，其中係將 該雷射光束偏振，而對準該被捕獲的CNT。 1 5 .如申請專利範圍第9項之控制裝置，進一步包含 一基材層，其中係將該基材層機能化，而使該CNT 無法移動。 1 6·如申請專利範圍第9項之控制裝置，其中係將該 雷射光束聚焦到具有複數個單壁CNT ( SWNT )的一多壁 CNT ( MWNT )，而操控該 MWNT。 1 7. —種控制系統，包含： 含有一奈米碳管（CNT )的一流體，該CNT對一捕 獲頻率起響應； 一雷射，用以將一雷射光束聚焦到該CNT，以便藉由 控制該雷射光束而操控該CNT ;以及 被置於該雷射與該流體之間的一光學組合件，用以調 變該雷射光束。 -16- 200529273 (4) 18.如申請專利範圍第1 7項之控制系統，其中該雷 射改變該雷射光束的頻率，以便配合捕獲頻率，而捕獲在 一第一流體層中的一捕獲部位之該CNT。 1 9 ·如申請專利範圍第1 8項之控制系統，其中該雷 射將該雷射光束的焦點位置自一第一位置改變至一第二位 置，而將該被捕獲的CNT自該第一層中之一第一部位移 到一第二層中之一第二部位。 2 0.如申請專利範圍第1 8項之控制系統，其中係以 關閉該雷射光束、阻隔該雷射光束、過濾該雷射光束以減 少雷射強度、改變該雷射光束的頻率、在該第二層中使用 具有不同的黏度或介電常數之一不同的流體媒介、以及移 動該雷射光束通過一液體-固體介面中之一種方式釋出該 被捕獲的CNT。 2 1 .如申請專利範圍第1 8項之控制系統，其中係在 具有不同黏度的該第一與第二層間之一介面上釋出該被捕 獲的CNT。 22 ·如申請專利範圍第1 8項之控制系統，其中係將 該雷射光束偏振，而對準該被捕獲的CNT。 23 .如申請專利範圍第1 7項之控制系統，進一步包 含： 一基材層，其中係將該基材層機能化，而使該CNT 無法移動。 24 .如申請專利範圍第1 7項之控制系統，其中係將 該雷射光束聚焦到具有複數個單壁CNT(SWNT)的一多 -17- 200529273 (5) 壁CNT(MWNT)，而操控該MWNT。200529273 (1) X. Patent application scope1. A control method including the following steps: focusing a laser beam in a carbon nanotube (CNT) in a fluid, the CNT responding to a capture frequency; and The focused laser beam is controlled to control the nano carbon tube (CNT). 2. The control method according to item 1 of the patent application range, wherein the control step includes the following steps: changing the frequency of the laser beam so as to match the capture frequency and capturing a capture in a first fluid layer in the fluid Site of the CNT. 3. The control method according to item 2 of the patent application range, wherein the control step includes the following steps: changing the focal position of the laser beam from a first position to a second position, and changing the captured CNT from the A first portion of the first layer is displaced to a second portion of a second layer in the fluid. 4. The control method according to item 2 of the patent application scope, wherein the control step includes the following steps: to turn off the laser beam, block the laser beam, filter the laser beam to reduce the laser intensity, and change the laser beam Frequency, using a different fluid medium having a different viscosity or dielectric constant in the second layer, and moving the laser beam through a liquid-solid interface to release the captured CNTs. 5. The control method according to item 2 of the scope of patent application, wherein the control step includes the following steps: -14- 200529273 (2) releasing the captured CNT on one of the interfaces between the first and second layers with different viscosities . 6. The control method according to item 2 of the patent application range, wherein the control step includes the following steps: • Polarize the laser beam 'and align it with the captured CNT. 7. The control method according to item 1 of the patent application scope, wherein the control step includes the following steps: 'Functionalize a substrate layer so that the CNT cannot move. · 8 · The control method according to item 1 of the patent application range, wherein the focusing step includes the following steps: focusing the laser beam onto a multi-walled CNT (MWNT) having a plurality of single-walled CNTs (SWNTs), and manipulating the MWNT. 9. A control device comprising: a fluid containing a carbon nanotube (CNT), the CNT responding to a capture frequency, and the CNT is controlled by a focused laser beam controlled by a laser. 〇 10. The control device according to item 9 of the application, wherein the laser changes the frequency of the laser beam so as to match the capture frequency to capture the CNT at a capture site in a first fluid layer. 11. The control device according to item 10 of the patent application range, wherein the laser beam changes the focal position of the laser beam from a first position to a second position, and the captured CNTs are moved from the first position to the second position. A first part of one layer is displaced to a second part of a second layer. 1 2 · If the control device of the scope of patent application No. 10, it is -15-200529273 (3) Turn off the laser beam, block the laser beam, filter the laser beam to reduce the laser intensity, change the The frequency of the laser beam, the use of a different fluid medium with a different viscosity or dielectric constant in the second layer, and moving the laser beam through a liquid-solid interface to release the captured CNT. 1 3. The control device according to item 10 of the patent application scope, wherein the captured CNTs are released on an interface between the first and second layers having different viscosities. 14. The control device according to item 10 of the patent application scope, wherein the laser beam is polarized and aligned with the captured CNT. 15. The control device according to item 9 of the scope of patent application, further comprising a substrate layer, wherein the substrate layer is functionalized so that the CNT cannot move. 16. The control device according to item 9 of the scope of patent application, wherein the laser beam is focused on a multi-walled CNT (MWNT) having a plurality of single-walled CNTs (SWNTs), and the MWNT is controlled. 1 7. A control system comprising: a fluid containing a nano carbon tube (CNT), the CNT responding to a capture frequency; a laser for focusing a laser beam onto the CNT for borrowing The CNT is controlled by controlling the laser beam; and an optical assembly placed between the laser and the fluid to modulate the laser beam. -16- 200529273 (4) 18. The control system according to item 17 of the patent application scope, wherein the laser changes the frequency of the laser beam so as to match the capture frequency and capture a capture in a first fluid layer Site of the CNT. 19 · The control system according to item 18 of the patent application scope, wherein the laser changes the focal position of the laser beam from a first position to a second position, and the captured CNTs are moved from the first position. A first portion of a layer is displaced to a second portion of a second layer. 20. The control system according to item 18 of the scope of patent application, wherein the laser beam is turned off, the laser beam is blocked, the laser beam is filtered to reduce the laser intensity, the frequency of the laser beam is changed, The second layer uses one of different fluid media having different viscosities or dielectric constants, and the captured CNTs are released by moving the laser beam through a liquid-solid interface. 2 1. The control system according to item 18 of the scope of patent application, wherein the captured CNTs are released on an interface between the first and second layers having different viscosities. 22 · The control system according to item 18 of the patent application scope, wherein the laser beam is polarized and aimed at the captured CNT. 23. The control system according to item 17 of the scope of patent application, further comprising: a substrate layer, wherein the substrate layer is functionalized so that the CNT cannot move. 24. The control system according to item 17 of the scope of patent application, wherein the laser beam is focused to a multi-unit with a plurality of single-walled CNTs (SWNTs) -17- 200529273 (5) walled CNTs (MWNTs) and controlled The MWNT. -18--18-
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